Tire Size 245/75r16 vs 245/70r16
The main difference between 245/75R16 and 245/70R16 tires is the aspect ratio. The aspect ratio measures the height of the tire’s sidewall relative to its width. A higher aspect ratio means a taller sidewall, while a lower aspect ratio means a shorter sidewall.
245/75r16 vs 245/70r16
Take a look at this convenient comparison table to gain a clear understanding of the distinctions between tire sizes 245/75R16 and 245/70R16.
| Feature | 245/70r16 | 245/75r16 | Difference |
|---|---|---|---|
| Diameter inches | 29.5 (749.4) | 30.47 (773.9) | 0.96 (24.5) |
| Width inches | 9.65 (245) | 9.65 (245) | 0 (0) |
| Circum. inches) | 92.69 (2354.31) | 95.72 (2431.28) | 3.03 (76.97) |
| Sidewall Height | 6.75 (171.5) | 7.23 (183.75) | 0.48 (12.25) |
| Revolutions | 683.57 (424.75) | 661.93 (411.31) | -21.64 (-13.45) |
Overall Diameter
The overall diameter is one of the most crucial aspects when comparing tire sizes. The 245/75r16 tire boasts an overall diameter of 30.47 inches (773.9 mm), while the 245/70r16 tire measures 29.5 inches (749.4 mm) in diameter.
The difference of approximately 1 inch (24.5 mm), though seemingly insignificant, equates to a 3.3% increase in size. As seen in the 245/75r16 tire, a larger overall diameter allows for better traction and improved performance on off-road terrain.
However, this may also lead to decreased acceleration due to the increased rotational mass. On the other hand, the smaller diameter of the 245/70r16 tire might offer slightly better acceleration and a smoother ride on well-paved roads.
Section Width
Interestingly, both tires share the same section width of 9.65 inches (245 mm), maintaining an identical contact patch with the road. This means both tires should offer similar grip levels, assuming they have the same construction and tread pattern.
Circumference
The circumference of a tire directly influences the distance covered in a single tire rotation. The 245/75r16 tire features a circumference of 95.72 inches (2431.28 mm), while the 245/70r16 tire has a smaller circumference of 92.69 inches (2354.31 mm), a difference of 3.03 inches (76.97 mm) or 3.3%.
A larger circumference means the vehicle will cover more ground per wheel rotation, leading to less engine rpm for a given speed, potentially increasing fuel efficiency on the highway. In contrast, a smaller circumference might result in better responsiveness and agility at lower speeds.
Sidewall Height
Sidewall height is another distinguishing characteristic between these two tire sizes. The 245/75r16 has a taller sidewall height of 7.23 inches (183.75 mm), compared to the 245/70r16’s 6.75 inches (171.5 mm)—a difference of 0.48 inches (12.25 mm) or 7.1%.
A tire with a taller sidewall, like the 245/75r16, provides better ride comfort due to its greater ability to absorb road shocks. However, it may suffer from slightly increased lateral flex during sharp turns.
Conversely, a lower sidewall height tire, like the 245/70r16, would offer more precise steering feedback and stability at the cost of comfort.
Revolutions Per Mile
The revolutions per mile metric tells us how many times a tire needs to rotate to cover a mile. Here, the 245/75r16 tire requires fewer revolutions (661.93) compared to the 245/70r16 (683.57)—a difference of -21.64 revolutions or -3.2%.
Fewer revolutions per mile translate into lower engine RPM for a given speed, reducing fuel consumption and engine wear. In contrast, more revolutions per mile could offer better acceleration and braking responsiveness.
Wheel Size
Both 245/70r16 and 245/75r16 tire sizes are designed for 16-inch wheels, indicated by the ‘r16’ in their designations. The construction type, indicated by the ‘r’ (for radial), is also the same.
Radial tires are the most common type of tire construction, known for their durability, improved handling, and ride comfort.
Alternative Tire Size of 245/70r16
The overall diameter of the replacement tires should not deviate more than 3% from that of the original tires.
| Tire Size | Overall Diameter | Difference |
|---|---|---|
| 215/75R16 | 28.7″ (728 mm) | -2.9% |
| 205/80R16 | 28.9″ (734 mm) | -2.1% |
| 235/70R16 | 29″ (736 mm) | -1.9% |
| 275/60R16 | 29″ (736 mm) | -1.9% |
| 255/65R16 | 29.1″ (738 mm) | -1.6% |
| 225/75R16 | 29.3″ (744 mm) | -0.8% |
| 285/60R16 | 29.4″ (748 mm) | -0.3% |
| 215/80R16 | 29.5″ (750 mm) | 0% |
| 265/65R16 | 29.5″ (750 mm) | 0% |
| 247/70R16 | 29.6″ (752 mm) | 0.3% |
| 315/55R16 | 29.6″ (752 mm) | 0.3% |
| 235/75R16 | 29.8″ (758 mm) | 1.1% |
| 275/65R16 | 30.1″ (764 mm) | 1.9% |
| 255/70R16 | 30.1″ (764 mm) | 1.9% |
| 215/85R16 | 30.4″ (772 mm) | 2.9% |
Alternative Tire Size of 245/75r16
The overall diameter of the replacement tires must be no more than 3% different from that of the original tires.
| Tire Size | Overall Diameter | Difference |
|---|---|---|
| 315/55R16 | 29.6″ (752 mm) | -2.8% |
| 247/70R16 | 29.6″ (752 mm) | -2.8% |
| 235/75R16 | 29.8″ (758 mm) | -2.1% |
| 255/70R16 | 30.1″ (764 mm) | -1.3% |
| 275/65R16 | 30.1″ (764 mm) | -1.3% |
| 215/85R16 | 30.4″ (772 mm) | -0.3% |
| 285/65R16 | 30.6″ (776 mm) | 0.3% |
| 265/70R16 | 30.6″ (778 mm) | 0.5% |
| 235/80R16 | 30.8″ (782 mm) | 1% |
| 345/55R16 | 30.9″ (786 mm) | 1.6% |
| 225/85R16 | 31″ (788 mm) | 1.8% |
| 295/65R16 | 31.1″ (790 mm) | 2.1% |
| 275/70R16 | 31.2″ (792 mm) | 2.3% |
Our Observation
The choice between 245/75r16 and 245/70r16 largely depends on your driving preferences and conditions. If your driving is primarily highway or off-road, and you desire a more comfortable ride with potential fuel savings, the 245/75r16 might be a better choice with its larger overall diameter and taller sidewall height.
However, if you value sharper handling, responsiveness and spend most of your time in the city driving, the 245/70r16 is a more suitable choice. Remember that fitting different tire sizes can impact the accuracy of your speedometer and odometer, as these devices are calibrated based on the vehicle’s original tire size.
Always consult with a professional before making changes to your vehicle’s tire size. It is crucial to understand that optimal safety and performance can only be achieved when the tires match the specifications recommended by the vehicle manufacturer.
Meet Caitlin McCormack, a Tire Size Expert and Blogger Passionate About Everything Related to Tires. With Years of Experience in the Tire Industry, Caitlin Has Become an Expert in Tire Sizes and Their Impact on Vehicle Performance.